A:西周
B:秦朝
C:汉朝
D:唐朝
____ is known to us all is that the 2010 Asian Games took place in Guangzhou.
如图所示,在杠杆AOB的A端挂一个重为GA的物体,B端挂—个重为GB的物体时,杠杆处于平衡状态,若AO=BO,杠杆自身重力不计,则( )
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